The current cellular Long Term Evolution (LTE) standard supports flexible bandwidth (BW), from 1.4 MHz up to 20 MHz, and even wider bandwidths using carrier aggregation techniques. In order for a wireless device—e.g., a “UE” in 3GPP parlance—to connect to a network (NW) node, such as an eNodeB or other base station, the wireless device must determine the cell carrier frequency as well as the system bandwidth to use. Furthermore, in current LTE standards there is a requirement that the NW node and the wireless device support and connect using the same system BW. Hence, the wireless device must search for relevant control messages over the entire system BW of the NW.
For the upcoming new radio-access technology in 5G, denoted NR herein, a more generic approach is desirable w.r.t the system bandwidths of respective nodes. NR should support multiple types of wireless devices. A range of device types includes, for example, high-end Mobile Broadband (MBB) devices capable of supporting system BWs up to several GHz, down to low-cost, low-power Machine Type Communication (MTC) devices, which may support BWs of 100 kHz or perhaps a few MHz.
Hence, one of the capabilities desired NR systems is flexibility in allocating “scheduling” BWs to respective wireless device. Here, scheduling BW is the BW determined and signalled by the network node to the wireless device such that the wireless device may apply a receive BW in which it may search for a control channel. In particular, in contrast to prior releases of LTE (and other, earlier-generation network standards), NR systems should have the ability to allocate a “scheduling” bandwidth to any given device that lies anywhere within the overall system BW configured for the supporting NW node. The allocated scheduling bandwidth may equal or be less than the radio receiver BW supported by the device.
eMTC is part of Release 13 by the 3GPP and, among other things, provides for lower bandwidths in the uplink and downlink, lower data rates and reduced transmit power, all benefiting at least certain types of MTC device. While the eMTC enhancements allow for an MTC device to operate on a BW smaller than the system BW of the supporting NW node it connects with, the approach lacks the flexibility needed for NR systems because it is based on using a fixed 1.4 MHz BW.
Hence, it is recognized herein that there remains a need for a method and apparatus to provide the signalling needed between NR networks and the devices operating in them, to support flexible scheduling BW allocations.